Fix false positive: return Any from a function declared to return object (#8011)

TH3CHARLie · ilevkivskyi · commit 253bdb5ce153 · 2019-11-26T14:27:48.000Z
Resolves #8008
diff --git a/mypy/checker.py b/mypy/checker.py
@@ -3036,7 +3036,9 @@ def check_return_stmt(self, s: ReturnStmt) -> None:
                         and not self.current_node_deferred
                         and not is_proper_subtype(AnyType(TypeOfAny.special_form), return_type)
                         and not (defn.name in BINARY_MAGIC_METHODS and
-                                 is_literal_not_implemented(s.expr))):
+                                 is_literal_not_implemented(s.expr))
+                        and not (isinstance(return_type, Instance) and
+                                 return_type.type.fullname == 'builtins.object')):
                         self.msg.incorrectly_returning_any(return_type, s)
                     return
 
diff --git a/test-data/unit/check-basic.test b/test-data/unit/check-basic.test
@@ -466,3 +466,11 @@ a = (a.A(), A())
 a.x  # E: "Tuple[a.A, b.A]" has no attribute "x"
 
 [builtins fixtures/dict.pyi]
+
+[case testReturnAnyFromFunctionDeclaredToReturnObject]
+# flags: --warn-return-any
+from typing import Any
+
+def f() -> object:
+    x: Any = 1
+    return x
